Method of manufacturing a concrete plank



March 9, 1965 s. A. VANDER HEYDEN 3,172,932

METHOD OF MANUFACTURING A CONCRETE PLANK 5 Sheets-Sheet 1 Filed Dec. 29, 1960 INVEN TOR. ice/men 4, l/wzeAwz/v W, mm lrraelvzn',

March 9, 1965 B. A. VANDER HEYDEN 3,172,932

METHOD OF MANUFACTURING A CONCRETE PLANK Filed Dec. 29, 1960 3 Sheets-Sheet 2 QM,MLJW4FM March 9, 1965 B. A. VANDER HEYDEN 3,172,932.

METHOD OF MANUFACTURING A CONCRETE PLANK Filed Dec. 29, 1960 3 Sheets-Sheet 3 United States Patent 3,172,932 RETHGD (ll MANUFACTURING A CQNCPJETE BLANK. Bernard A. Vander- Heydeu, 8239 W. Edge-iron Ave, Milwaukee, Wis. Fiied Dec. 29, 196i der. No. 79,381 18 Claims. (rill. 264-223} This invention relates to a method of manufacturing a concrete plank.

The plank comprises prefabricated blocks having aligned passages near the tension face and/ or the compression face of the plank to receive the reinforcing rods, access ports being provided in certain of the blocks to open from the face or side of the block for the introduction of cementitious grout which will embed the reinforcing steel and key it to several blocks. The blocks are maintained under compression until the grout solidifies about the reinforcing rods. The compression used is sufiicient so that the relief of compression permits slight expansion of the blocks to pare-stress the reinforcing rods. Further camber may be provided by assembling the plank upon a table which is slightly arched so that the tendency of the crowned plank to flatten when removed from such table and supported at its ends provides the desired further pre-stress.

The unit blocks assembled to make a plank in accordance with the present invention are not identical, each with another. A selected block or blocks intermediate the ends of the plank with or without channels (open or enclosed) in their faces has ports opening either from such channels or from the sides of the block into the passages provided for the reinforcing rods. The number of such special blocks varies according to the length of the plank, openings at such intervals as to facilitate and assure the proper distribution of the grout to reach every portion of the internal aligned passages in which the reinforcing steel is dispose In some types of planks, it may be desired to provide open or enclosed channels along the top of the plank to receive :additionfl steel. In such cases, the filling nozzles may have supplemental plates to keep the grout from spreading along these channels While it is being forced down through the ports leading to the internal passages above described.

These aligned passages are not of uniform cross sec tion but are tapered in each block, whereby the anchorage of the grout with respect to each individual block is further assured. These tapered passages hold the reinforcing steel free of the passage and allow grout to completely surround it.

As compared with previously known pressure grouting of concrete planks through the ends of the planks, this system of grouting through transverse ports has many advantages in the way of better distribution, higher quality and lower cost grouting, lower requirement, and positive assurance of bond. The ports provided at intervals along the present plank not only reduce power requirements but permit placement of st-irrups connecting upper and lower reinforcing steel. Also, it becomes unnecessary to remove the grouting nozzle from the path of discharge of the completed plank, as is the case when the nozzle is engaged with the forward end thereof. In the practice of the present invention, a relatively slight movement of the grouting nozzle is required to clear it from the plank to permit resumption of longitudinal plank movement.

Other features of the invention will more clearly appear from the following disclosure thereof.

In the rawings:

the object being to provide grout-receiving ice FIG. 1 is a diagrammatic plan View of an installation for the practice of the invention.

FIG. 2 is a detail view in perspective of one of the special prefabricated blocks used to facilitate transverse grouting of the reinforcing steel.

FIG. 3 is a view on a reduced scale taken on line 3--3 of FIG. 2.

FIG. 3a is a view in cross section through a plank, showing a stirrup in place to connect reinforcing rods at two levels.

FIG. 4 is a block designed to facilitate the application of top reinforcing steel in addition to the steel normally used adjacent the lower or compression face of the block.

FIG. 5 is a View in perspective showing a prefabricated block normally used for most of the length of the plank.

1G. 6 is a fragmentary view in perspective showing blocks assembled with each other and in compression with reinforcing steel, portions being broken away.

FIG. 7 is a view similar to FIG. 6 showing a modified organization of blocks.

FIG. 8 is a view taken in longitudinal section to the end blocks on the center plane of the plank and to the intermediate blocks.

FIG. 9 is :a view taken in section through a completed plank on a line indicated at 99 in FIG. 6.

10 is a view taken in section through a com pieted plank according to the assembly of FIG. 7 on the line itiltl of FIG. 7.

FIG. 11 is a view in perspective showing a further modified prefabricated block for use in planks embodying the present invention.

FIG. 12 is a view in perspective fragmentarily illus .trating portions of a plank and portions of la grouting head embodying the invention, parts being broken away.

FIG. 13 is a view taken in transverse section on the line 13- 13 of FIG. 12.

PEG. 14 is a detail view inperspective showing a speicial plate prettier-ably employed for confining the grout when the prefabricated blocks are of the type shown in FiGS. 4 and 7.

In the general diagrammatic showing of FIG. 1, a source of concrete blocks is represented at 15. It is immaterial whether this is a concrete block machine, or a grinder or other means of facing the ends of the blocks, or merely a loading table. A conveyor 16 leads from the source 15 into proximity to an assembly table 1'7 on which the blocks are aligned and receive the reinforcing steel 1'8, which becomes a permanent part of the plank, and a tension bar 19 which is applied temporarily as a means of pro-stressing the plank.

The plank structure shown in FIG. 6 is a preferred embodiment of the invention. It comprises a number of blocks such as that shown at 20 (see FIG. 5). Blocks such as that shown at 21 (see FIG. 2) are used at the center point as well as the second unit in from either end, or they can be used every few feet in positions intervening between blocks iii (see FIG. 6). If the plank is to have reinforcing steel adjacent both its upper and its lower faces, blocks 2% shown in FIG. 4 may be substituted for blocks 2%). These blocks have continuous channels 2? and 395 like those used in block 21, into which supplemental reinforcing steel may be laid, the registering channels being now continuous throughout the length of the plank. The grouting head hereinafter described wiil deposit grout in the channels 29 and 30 of the blocks 2% but such grout will penetrate into the deep passages 22 and 23 only when one of the blocks 21 passes beneath the grouting head.

Blocks of all types have internal passages 22 and 23 to receive the reinforcing steel 18. As best shown in FIG. 3, these openings taper to facilitate withdrawal of the cores and not enough to interfere with the flow of the 3: grout. The taper also provides a chair to support the steel so that the grout may flow around and embed it.

Additionally, the sharply tapering form of the passage, which is considerably larger in cross section at one end of the block than at the other, provides support for the reinforcing steel at the points where the passages of the several blocks are of small cross section, while holding the reinforcing steel 18 free of the block at all other points where the passages are of larger cross section, thus fully exposing the steel to the pressure-injected grout in which it is to be imbedded, and whereby the steel is to be bonded to the blocks.

The respective blocks have their end faces 24 and 25 finished, as by grinding or other means to assure that the face will be smooth, reasonably dense and reasonably planiform. Preferably, the end faces converge slightly toward the lower faces 26 of the blocks, the convergence being indicated by arrows at 27 in FIG. 3. The faces 26 are at the tension side of the completed plank. The purpose of this, where used, is to provide a slight arch or crown for the resulting plank as shown by the arrows 28 in FIG. 8.

In the case of the block 26, the internal passages 22 and 23 which receive the reinforced steel 18 are completely closed. In the case of the block 21, as separately illustrated in FIG. 2, there are parallel upwardly opening channels 29 and 30 to the face 31 normally uppermost and normally under compression in the completed plank. From the channels 29, 30, ports 33, 34 open downwardly into the internal passages 22 and 23, such ports being designed to admit into the passages grout under pressure that will flow through the passages of the particular block 21 and contiguous blocks 26 until the reinforcing steel in the aligned passages is completely embedded. As later explained, the holes may be cored or drilled through any surface as shown by ports 330 and 340 in FIG. 11.

When the blocks are assembled on the table 17, the tensioning bar 19 is threaded through the aligned openings 35 and through compression plates 36 and 37 which engage the end faces of the terminal blocks of the plank. A plug 38 adjustable on the pro-stress bar 19 engages the pressure plate 36 and a wedge 39 inserted through a loop 40 at the other end of the bar engages the pressure plate 37 as shown in FIGS. 6, 7 and 8.

The assembly is now moved through the position shown in dotted lines at 41 onto a conveyor 42 whereby it may be passed through a grouting head 45 separately illustrated in FIGS. 12 and 13.

The grouting head 45 comprises a frame 46 which straddles the conveyor 42 and includes longitudinal chanr nels providing a track or way having rails 47, 48 upon which the carriage 50 is reciprocable above and parallel to the path of advance of the blocks assembled along the pre-stress bar 19 to receive the grout. The carriage includes a transverse member 51 and a pair of longitudinal angles 52 and 53 which are provided with supporting rollers 54 and guide rollers 55 engaging the tracks or ways 47, 48 for the support and positioning of the carriage.

Mounted on the carriage 50 is a vertically operating ram having a reciprocable plunger 61 supporting a yoke 62 on which a nozzle pipe 63 is mounted. This pipe is closed at its end 64 and it communicates laterally with a pair of nozzles at 65 each of which is encircled by a packing gasket 66. The nozzles are so spaced as to register with the channels 29 and 3d of the blocks 21 or 2450 assembled in the plank. As clearly shown in FIG. 12, the yoke 62 includes elongated members 67, 68 of sufficient length to span one of the channeled blocks 21, the packing gasket 66 being desirably similarly elongated so as to provide a seal from end to end of each of the channels 29 and 30 in a block of the type shown at 21 where this block intervenes between other blocks of the type shown at 20 (see FIG. 12).

When the block 21 of this type is registered beneath the yoke, the ram is hydraulically operated (by means not shown) to lower the yoke to the dotted line position shown in FIG. 13, thereby engaging the sealing gaskets 66 about the channels 29 and 30, with which the nozzles 65 now communicate. Thereupon the pump 63 is operated to deliver grout from hopper 69 under pressure through a flexible hose 70 to the nozzle pipe 63 for discharge through the nozzle 65, the pressure being adequate to force the grout down through the ports 33 and 34 into the passages 22 and 23 of the plank assembly. The feed of grout is continued until the said passages are completely filled about the reinforcing rods for such portion of the plank assembly as is served through the particular parts 33 and 34 into which grout is presently being fed under pressure. After an interval sufiicient to assure a complete imbedding of the reinforcing seal in this portion of the plank assembly, the ram 61 is reversed to lift the nozzle yoke 62. The plank assembly is then advanced to register the next special block 21 with the nozzle. Thereupon the nozzle yoke is lowered and the operation is repeated. Inasmuch as the special blocks 21 are used at relatively short intervals throughout plank assembly, much less pressure is required and there is much greater assurance of complete envelopment of the reinforcing steel than would be the case if the grout could be injected only at the end of the whole series of blocks comprising the plank.

The passages in the blocks offer so much resistance to the flow of the grout that it is not essential to plug the passages at either end of the series of blocks. The appearance of grout at the exposed end of the terminal block will assure the operator that the entire passage is full of the pressure-delivered grout and the reinforcing steel is completely imbedded. However, in practice, the plates 36 and 37 do close the passages at the end of the series as shown in FIGS. 6, 7 and 8.

The mounting of the carriage 50 on rollers for movement longitudinally of the ways 47 and 48 of the grouting head 45 makes it possible either to manipulate the nozzle yokes into registry with the grout-receiving ports in the case of a step-by-s-tep longitudinal advance of the plank assembly or, optionally, it makes it possible to maintain the plank assembly in continuous longitudinal movement, the nozzle, yoke and carriage moving with the plank assembly during the period of grout injection through the ports into the passages in which the reinforcing steel is disposed to be imbedded by the grout injected therein.

Ordinarily, the step-by-step motion is to be preferred because of the fact that the plank is cambered or arched by the pressure of the clamping bar as exerted on the ends of the plank by the plates 36 and 37. If the plank is thus cambered or arched in advance, then, obviously, the grouting head will have to change its level somewhat as the plank progresses beneath it. There is no such problem if the grouting head simply moves vertically to and from grouting position during the dwell of an intermittently advancing plank.

If the channels 29 and 30 are provided throughout the length of a series of blocks such as those shown at 200, then the gaskets will not provide an adequate seal about the nozzles. They are able to do so in the structure above described because each of the channels 29 and 30 in each of the blocks 21 is closed at its end by one of the unchanneled blocks 20. Therefore, if blocks 200 are substituted for the blocks 20, it is preferred to provide the nozzle with a steel plate such as that shown at 72 in FIG. 14. This plate has slots at 73 and 74 in registry with the nozzles and some of the material blanked from such slots is turned downwardly to provide tongues at 75 which fit the channels 29 and 39 to dam these channels whereby to require the pressure-fed grout to flow downwardly through the ports 33 and 3d of the special blocks 21 as above describtd. The rest of the length of the channels 39 and 31 in the blocks 2% can either be pressure grouted with grout supplied thereto by gravity during movement of the assembly beneath the nozzles or the channels may be filled from the hopper 76.

Instead of providing channels 2%, 30 to register with the ports 33 and 34-, I may use blocks of the type shown at 291 in FIG. 11 in which the ports 33% and 340 are either cored or drilled to extend through any outer surface of the block to receive grout from the pressure nozzle as above described.

FIG. 9 shows the reinforcing steel 18 imbedded in grout 89 which fills the passages 22 and 2-3 and is bonded to the block as well as to the steel.

FIG. is a cross section of the assembly of FIG. 7 wherein the special blocks 2% are used between spaced blocks of the type shown at 21. The intention here is to provide additional reinforcing steel as shown at 1843 in P16. 10, this being imbedded in that portion of the grout 81 which fills channels 29 and 3t and extends downwardly through the filling ports 33 and 34 to imbed the steel 13 in the holes 22 and 23.

As shown in FIG. 3a, any such ports may receive a stirrup 913 which is imbedded in the grout 81 and connects to rod l3 and to the reinforcing steel 189, if any, to resist diagonal tension.

FIG. 10 is a cross section of the assembly of FIG. 7 wherein the special blocks 2% are used between spaced blocks of the type shown at 21. The intention here is to provide additional reinforcing steel as shown at 189 in EEG. 10, this being imbedded in that portion of the grout 81 which fills channels 29 and 3t) and extends downwardly through the filling ports 33 and 34 to embed the steel 18 in the holes 22. and 23.

In some aspects of the invention as already described, it is not important what is done with the grouted plank assemblies after the grout is in place. However, in the preferred practice of the invention, the assemblies continue their forward movement from the grouting head to the rollover station shown at the left in PEG. 1 where any ap ropriate rollover cradles diagrammatically illustrated at 83 pick up each assembly from the full line position and invert it as shown by the arrow 84 to the position shown in dotted lines at SS in FIG. 1. The invertm assembly is then placed on any appropriate supports as and S7, 33 for curing, while still under tension of the preress bars 19. In practice, the supports 86, 87 and 88 are gravity conveyors, the conveyors 86 and 88 being somewhat higher in level than conveyor 87 to accommodate the camber of the inverted plank. In order that the plank may operate freely along the roller conveyors, each plank is preferably supported on strips 89 of wood or metal which act as runners. It is also possible to have a pallet for each plank which has the required camber and supports the plank throughout its length, but this is not shown, no claim being made thereto.

The conveyors ordinarily support the planks in a curing chamber or kiln for a number of hours. This, also, is conventional practice and the kiln is not illustrated, no claim being made thereto.

After the plank is cured, the bars 19 are removed and the slight resulting expansion consequent upon release of the compression exerted by bars 19 will tension or prestress the reinforcing steel grouted into place as above described.

I claim:

1. A method of making concrete planks which comprises the steps of prefabricating concrete blocks having internal passages for reinforcing steel, finishing the faces of said blocks to render them smooth and fiat, horizontally assembling an elongated row of such blocks in alignment with their respective smooth fiat finished faces in abutment and their several steel-receiving passages in registry, inserting the reinforcing steel in said passages, providing in certain of said blocks at intervals along the length of the row ports each communicating with the internal passage from an external surface of one of the blocks, subjecting the blocks so assembled to pressure exerted longitudinally of the row, pressure feeding grout through said ports successively in quantity sufficient to envelop the steel through the row and to bond it to the blocks through which it passes, the pressure to which the blocks are subject in the row being sufiicient to hold said finished faces in grout-confining engagement with each other, and advancing the elongated row of such blocks between the feeding of grout through successive ports while maintaining the pressure on the blocks of said row, and continuing to maintain said pressure until the grout has set.

2. The method recited in claim 1 in which said ports are prefabricated in certain of said blocks.

3. The method recited in claim 1 in which said ports are drilled in certain of said blocks.

4. The method of claim 1 in which the introduction of grout through said ports takes place at a predetermined point, the longitudinal advance of the row of said blocks being a step-by-step advance to register successive ports to receive the grout at said point.

5. A method of manufacturing concrete planks having internal reinforcing steel, such method consisting in the steps of prefabricating blocks having internal passages adjacent their corresponding faces to receive such steel, facing the ends of the blocks with a grinder to render them flat and smooth, aligning the blocks in an elongated row with the said passages in registry, with their face ends in abutment, introducing steel into the registering passages of the aligned blocks, making ports aifording access to said passages at intervals throughout the length of the series of aligned blocks, connecting the series of aligned blocks together under pressure exerted longitudinally of said series, advancing the row of connected aligned blocks in a direction longitudinally of the row past a grouting station, and introducing grout under pressure at said station through each port into the passages about the steel therein, whereby grout is introduced at a plurality of points in said row of connected blocks, and maintaining the blocks of said row under said pressure until the grout has set.

6. The method recited in claim 5 in which the advance is a step-by-step advance with intervening dwells and the introduction of grout is intermittent and occurs during dwells in the course of such advance.

7. The method recited in claim 5 in which the injection of grout into said ports at said station occurs during continued advance of said series of blocks.

8. The method recited in claim 5 including as a further step the prefabricating of said blocks to provide channels in certain of the blocks in the faces thereof which are opposite the faces to which said passages are adjacent, the ports being provided from said channels to said passages.

9. The method recited in claim 8 in which substantially all of said blocks are provided with corresponding channels and additional reinforcing steel is laid in said corresponding channels and imbedded in grout filling said channels as well as extending through said ports and filling said passages.

10. The method recited in claim 8 including the further step of at least partially damming said channels during pressure injection of grout through said ports to require the pressure-injected grout to flow through said ports into said passages.

References Cited in the file of this patent UNITED STATES PATENTS 1,477,665 Richman Dec. 18, 1923 (Qther references on following page) 

5. A METHOD OF MANUFACTURING CONCRETE PLANKS HAVING INTERNAL REINFORCING STEEL, SUCH METHOD CONSISTING IN THE STEPS OF PREFABRICATING BLOCKS HAVING INTERNAL PASSAGES ADJACENT THEIR CORRESPONDING FACES TO RECEIVE SUCH STEEL, FACING THE ENDS OF THE BLOCKS WITH A GRINDER TO RENDER THEM FLAT AND SMOOTH, ALIGNING THE BLOCKS IN AN ELONGATED ROW WITH THE SAID PASSAGES IN REGISTRY, WITH THEIR FACE ENDS IN ABUTMENT, INTRODUCING STEEL INTO THE REGISTERING PASSAGES OF THE ALIGNED BLOCKS, MAKING PORTS AFFORDING ACCESS TO SAID PASSAGES AT INTERVALS THROUGHOUT THE LENGTH OF THE SERIES OF ALIGNED BLOCKS, CONNECTING THE SERIES OF ALIGNED BLOCKS TOGETHER UNDER PRESSURE EXERTED LONGITUDINALLY OF SAID SERIES ADVANCING THE ROW OF CONNECTED ALIGNED BLOCKS IN A DIRECTION LONGITUDINALLY OF THE ROW PAST A GROUTING STATION, AND INTRODUCING GROUT UNDER PRESSURE AT SAID STATION THROUGH EACH PORT INTO THE PASSAGES ABOUT THE STEEL THEREIN, WHEREBY GROUT IS INTRODUCED AT A PLURALITY OF POINTS IN SAID ROW OF CONNECTED BLOCKS, AND MAINTAINING THE BLOCKS OF SAID ROW UNDER SAID PRESSURE UNTIL THE GROUT HAS SET. 